The major objectives of this research project involve the determination of the sub-cellular components which regulate the motility and social behavior of cultured normal and transformed cells. The functions of the major components of the cytoskeleton and cytomusculature are being emphasized. These components include microfilaments, intermediate (approximately 10 nm) filaments and microtubules. These cytoplasmic fiber systems are thought to be responsible for controlling many aspects of the behavior of cultured cells including adhesion, spreading, surface topology, shape formation, locomotion, division and contact inhibition. The long-term goal of these studies is to gain new insight into the mechanisms involved in the cellular basis of transformation to the neoplastic state which ultimately results in malignant tumor formation and metastasis. Experimental approaches involved in relating structure and function in this proposal include microscopical, physiological, immunological and biochemical techniques.